A saw blade of the kind mentioned above is known from DE 43 24 411 A1. The saw blade comprises a basic body having unset and set teeth the tips of which are made from a metal being harder than the material of the basic body. A material for the tips is tungsten carbide for example but also high-speed steel. The teeth are arranged in recurring groups or cycles. The group having the smallest number of teeth would be a group of three teeth, one unset leading tooth and two trailing teeth being set to the left and right respectively. The leading tooth has a height which is larger than the height of each of the trailing teeth. The leading tooth is provided with a phase, i.e. comprises a cutting-edge section in the middle extending perpendicular to a longitudinal center plane of the saw band followed symmetrically by an inclined section left and right. The difference between the height of the leading tooth and the heights of the trailing teeth and the phase angle are designed large so that the projection view of the teeth in the running direction of the saw blade during work the inner edges of the trailing teeth lie in the circumference of the leading tooth and the outer edges of the leading tooth overly the trailing teeth partly so that the overlaid parts do not take cutting work during use. The cutting sections of all of the teeth normally are made by grinding, i.e. by a precise but costly forming step by which the two different heights result also.
A further saw blade of the type mentioned above is known from U.S. Pat. No. 4,727,788. The saw blade has recurring groups of teeth with one leading tooth and a number or trailing teeth. The leading tooth has the largest height and the heights in the group decrease, but can be constant also. The trailing teeth are set teeth in succession set left and right respectively to broaden the channel to be cut in the workpiece and to make it wider than the width of the basic body of the saw blade. The leading tooth may be provided with a phase also. The production of the teeth having different heights is performed by milling or by the use of a beating tool deforming the tips of the teeth in the running direction of the saw blade during use. This is followed by a grinding process in order to form the cutting sections of the teeth in the in different height levels. The part of the grinded cutting sections being effective during use decreases from tooth to tooth in the group as the height decreases so that the essential cutting work is done by the leading tooth, while the two trailing teeth broaden the channel to allow free cutting.
A saw blade having recurring groups of teeth is known from DE 33 00 791 C2. This saw blade has a first recurring group of teeth having a large common height and a second recurring group having a small common height. The first group of teeth comprises unset and set teeth. The second group of teeth comprises unset and set teeth. However, each group can have teeth of two different heights. Each tooth has a first and second rake angle being different from each other. Each tooth has a first and second clearance angle being different from each other. The two different rake angles and clearance angles provided at each single tooth can be made by plastic deformation of the tip of the tooth especially by displacing material of the tooth using a deformation device being driven in a sharp angle with respect to the running direction of the band. Doing this the height of the tooth is reduced at the same time. The amount of displacing can be controlled by adjusting the stroke of the deformation device. The forming of the teeth can be performed by milling and grinding also. A succession of teeth is formed by the plastic deformation of one tooth after the other. There is a height difference between the common large height of the teeth of the first group and the common small height teeth of the second group. There is also a difference between the common rake angle of the high teeth with respect to the low teeth and between the common clearance angle of the high teeth and the common clearance angle of the low teeth. Different depths and variable pitch may be applied also with respect to each of the groups. The plastic deformation of the high teeth is the same with respect to each high tooth. Thus, all of the high teeth after deformation have a common rake angle. It is not described whether the height difference between the high teeth and the low teeth results partly by profiling or by plastic deformation respectively.